Wireless login with secure proximity detection

ABSTRACT

After detecting an access-intent operation, an electronic device establishes a connection with a second electronic device using a communication protocol. The electronic devices exchange identifiers, and the second electronic device provides information specifying a preferred channel to use with a second communication protocol. Based at least in part on the preferred channel of the second electronic device and on communication contexts of the electronic devices, the electronic device selects a channel and transmits to the second electronic device information specifying the selected channel. The electronic device remotely accesses credential information based on the exchanged identifiers, and using the credential information, the electronic devices establish a secure connection via the selected channel using the second communication protocol. The electronic device determines a distance to the second electronic device using wireless ranging via the secure connection. When the electronic devices are proximate to each other, the electronic device can be unlocked.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 62/348,711, entitled “WIRELESS LOGIN WITH SECUREPROXIMITY DETECTION” filed Jun. 10, 2016, the content of which isincorporated herein by reference in its entirety for all purposes.

FIELD

The described embodiments relate, generally, to wireless communicationsamong electronic devices, including electronic devices and accesspoints, and techniques for wireless access authentication with anelectronic device using wireless communication and secure proximitydetection based on wireless ranging.

BACKGROUND

While a variety of authentication techniques are available, users oftenperform access authentication with many electronic devices (such aslegacy devices) using a so-called login technique. In particular, inresponse to a login prompt, a user may enter their login credentials,such as their username and password. If the username and password arevalid, the user is allowed to access the electronic device.

However, this approach to access authentication is often time-consumingand cumbersome. In addition, the login credentials are often insecure.For example, users often manually enter their credentials and they oftenchoose simple or obvious passwords that are easily cracked.

SUMMARY

Some embodiments relate to an electronic device that facilitateswireless access authentication. In particular, during operation, whenthe electronic device detects an access-intent operation, the electronicdevice may establish a connection with a second electronic device usinga communication protocol. The electronic device may receive, from thesecond electronic device, a second identifier of the second electronicdevice and information specifying a preferred channel of the secondelectronic device when using a second communication protocol. Moreover,the electronic device may select a channel based at least in part on thepreferred channel of the second electronic device and, in someembodiments, based at least in part on communication contexts of theelectronic device and the second electronic device. The electronicdevice may transmit to the second electronic device an identifier of theelectronic device and information specifying the selected channel. Theelectronic device may access, from a remote computer via a network (suchas the Internet), credential information associated with a user of theelectronic device and the second electronic device based at least inpart on the identifier and the second identifier. Furthermore, theelectronic device may establish, based at least in part on thecredential information, a secure connection with the second electronicdevice using the selected channel and the second communication protocol.Additionally, the electronic device may determine a distance to thesecond electronic device using wireless ranging via the secureconnection, and the electronic device may be unlocked or access to theelectronic device may be enabled based at least in part on thedetermined distance.

In some embodiments, after detecting the access-intent operation, theelectronic device performs a wireless scan for the second electronicdevice using the communication protocol, and the electronic devicediscovers the second electronic device.

The electronic device may detect the access-intent operation bydetecting an opening of a lid of the electronic device or detectinginput to a human-interface device associated with the electronic device(such as a mouse or a keypad). Moreover, the identifier may include amedia access control (MAC) address of the electronic device, and thesecond identifier may include a second MAC address of the secondelectronic device.

Furthermore, the communication contexts may include informationindicating whether the electronic device has a connection to the networkvia an access point, and information indicating whether the secondelectronic device has a second connection to the network via the sameaccess point or via an intermediate device. When the second electronicdevice has the second connection, the electronic device may select thepreferred channel as the channel.

The communication technique may be compatible with a Bluetooth Classicor Bluetooth Low Energy (BTLE) communication protocol, and the secondcommunication technique may be compatible with an Institute ofElectrical and Electronics Engineers (IEEE) 802.11 standardizedcommunication protocol.

Other embodiments include operation with or by the second electronicdevice. For example, during operation the second electronic device maytransmit advertisements using the communication protocol. The secondelectronic device may establish a connection with the electronic deviceusing the communication protocol, and the second electronic device maytransmit, to the electronic device, the second identifier of the secondelectronic device and information specifying the preferred channel ofthe second electronic device when using the second communicationprotocol. The second electronic device may receive the identifier of theelectronic device and information specifying the selected channel. Next,the second electronic device may access, from a remote computer via thenetwork (such as the Internet), credential information associated withthe user of the electronic device and the second electronic device basedat least in part on the identifier and the second identifier.Furthermore, the second electronic device may establish, based on thecredential information, the secure connection with the electronic deviceusing the selected channel and the second communication protocol.

Additionally, the second electronic device may determine the distance tothe electronic device using wireless ranging via the secure connection,and the second electronic device may transmit information that specifiesthe distance to the electronic device.

Other embodiments provide an interface circuit in the electronic deviceor the second electronic device.

Other embodiments provide a computer-program product for use with theinterface circuit in the electronic device and/or the second electronicdevice. This computer-program product includes instructions for at leastsome of the aforementioned operations performed by the interface circuitin the electronic device and/or the second electronic device.

Other embodiments provide a method for facilitating wireless accessauthentication. The method includes at least some of the aforementionedoperations performed by the interface circuit in the electronic deviceand/or the second electronic device.

This Summary is provided for purposes of illustrating some exemplaryembodiments, so as to provide a basic understanding of some aspects ofthe subject matter described herein. Accordingly, it will be appreciatedthat the above-described features are only examples and should not beconstrued to narrow the scope or spirit of the subject matter describedherein in any way. Other features, aspects, and advantages of thesubject matter described herein will become apparent from the followingDetailed Description, Figures, and Claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The included drawings are for illustrative purposes and serve only toprovide examples of possible structures and arrangements for thedisclosed systems and techniques for intelligently and efficientlymanaging communication between multiple associated user devices. Thesedrawings in no way limit any changes in form and detail that may be madeto the embodiments by one skilled in the art without departing from thespirit and scope of the embodiments. The embodiments will be readilyunderstood by the following detailed description in conjunction with theaccompanying drawings, wherein like reference numerals designate likestructural elements.

FIG. 1 is a block diagram illustrating an example of electronic devicescommunicating wirelessly.

FIG. 2 is a flow diagram illustrating an example of a method forfacilitating wireless access authentication using one of the electronicdevices in FIG. 1.

FIG. 3 is a flow diagram illustrating an example of communicationbetween electronic devices, such as the electronic devices of FIG. 1.

FIG. 4 is a block diagram illustrating an example of one of theelectronic devices of FIG. 1.

Table 1 presents an example of communication-context information for twoof the electronic devices of FIG. 1.

Table 2 presents an example of communication-context information for twoof the electronic devices of FIG. 1.

Note that like reference numerals refer to corresponding partsthroughout the drawings. Moreover, multiple instances of the same partare designated by a common prefix separated from an instance number by adash.

DETAILED DESCRIPTION

When an electronic device (such as a laptop computer) detects anaccess-intent operation (such as detecting an opening of a lid of theelectronic device, detecting touch via a keyboard, detecting movement ofa mouse, etc.), the electronic device may establish a connection with asecond electronic device (such as a smart-watch or a cellular telephone)using a communication protocol (such as BTLE). Using BTLE, theelectronic devices may exchange identifiers (such as MAC addresses ofthe electronic devices), and the second electronic device may provide apreferred channel to use with a second communication protocol (such asWi-Fi). Based at least in part on the preferred channel of the secondelectronic device and, in some embodiments, based at least in part oncommunication contexts of the electronic devices (such as informationindicating whether either or both are connected to a network, such asthe Internet, via one or more access points), the electronic device mayselect and transmit information specifying the selected channel. Theelectronic devices may remotely access credential information based onthe exchanged identifiers. Using the credential information, theelectronic devices may establish a secure Wi-Fi connection via theselected channel. In some embodiments, the electronic device maydetermine a distance to the other electronic device using wirelessranging via a secure connection. If the electronic devices are proximateto each other, the electronic device may be unlocked.

By facilitating wireless access authentication, this communicationtechnique may allow a user to rapidly access the electronic devicewithout the user entering or directly providing a password (and/or, moregenerally, login credentials). In addition, the secure connection in thecommunication technique can prevent spoofing and may protect the user'slogin credentials (such as the password). Consequently, thecommunication technique may improve the user experience when using theelectronic device or the other electronic device, and thus may increasecustomer satisfaction and retention.

Note that the communication technique may be used during wirelesscommunication between electronic devices in accordance with acommunication protocol, such as: an IEEE 802.11 standard (which issometimes referred to as Wi-Fi). For example, the communicationtechnique may be used with IEEE 802.11ax. However, this communicationtechnique may also be used with a wide variety of other communicationprotocols, and in electronic devices (such as portable electronicdevices or mobile devices) that can incorporate multiple different radioaccess technologies (RATs) to provide connections through differentwireless networks that offer different services and/or capabilities.

In particular, an electronic device can include hardware and software tosupport a wireless personal area network (WPAN) according to a WPANcommunication protocol, such as those standardized by the Bluetooth®Special Interest Group (in Kirkland, Wash.) and/or those developed byApple (in Cupertino, Calif.) that are referred to as an Apple WirelessDirect Link (AWDL). Moreover, the electronic device can communicate via:a wireless wide area network (WWAN), a wireless metro area network(WMAN) a wireless local area network (WLAN), near-field communication(NFC), a cellular-telephone or data network (such as using a thirdgeneration (3G) communication protocol, a fourth generation (4G)communication protocol, e.g., Long Term Evolution (LTE), LTE Advanced(LTE-A), a fifth generation (5G) communication protocol, or otherpresent or future developed advanced cellular communication protocol)and/or another communication protocol. In some embodiments, thecommunication protocol includes a peer-to-peer communication technique.

The electronic device, in some embodiments, can also operate as part ofa wireless communication system, which can include a set of clientdevices, which can also be referred to as stations, client electronicdevices, or client electronic devices, interconnected to an accesspoint, e.g., as part of a WLAN, and/or to each other, e.g., as part of aWPAN and/or an ‘ad hoc’ wireless network, such as a Wi-Fi directconnection. In some embodiments, the client device can be any electronicdevice that is capable of communicating via a WLAN technology, e.g., inaccordance with a WLAN communication protocol. Furthermore, in someembodiments, the WLAN technology can include a Wi-Fi (or moregenerically a WLAN) wireless communication subsystem or radio, and theWi-Fi radio can implement an IEEE 802.11 technology, such as one or moreof: IEEE 802.11a; IEEE 802.11b; IEEE 802.11g; IEEE 802.11-2007; IEEE802.11n; IEEE 802.11-2012; IEEE 802.11ac; IEEE 802.11ax, or otherpresent or future developed IEEE 802.11 technologies.

In some embodiments, the electronic device can act as a communicationshub that provides access to a WLAN and/or to a WWAN and, thus, to a widevariety of services that can be supported by various applicationsexecuting on the electronic device. Thus, the electronic device mayinclude an ‘access point’ that communicates wirelessly with otherelectronic devices (such as using Wi-Fi), and that provides access toanother network (such as the Internet) via IEEE 802.3 (which issometimes referred to as ‘Ethernet’). Note that the access point mayinclude a soft access point, in which software executing on anelectronic device (such as a computer or a cellular telephone) allowsthe electronic device to support Wi-Fi links with a small number ofassociated electronic devices (i.e., a soft access point may be a‘hotspot’ for the small number of associated electronic devices).

Additionally, it should be understood that the electronic devicesdescribed herein may be configured as multi-mode wireless communicationdevices that are also capable of communicating via different 3G and/orsecond generation (2G) RATs. In these scenarios, a multi-mode electronicdevice or user equipment (UE) can be configured to prefer attachment toLTE networks offering faster data rate throughput, as compared to other3G legacy networks offering lower data rate throughputs. For example, insome implementations, a multi-mode electronic device is configured tofall back to a 3G legacy network, e.g., an Evolved High Speed PacketAccess (HSPA+) network or a Code Division Multiple Access (CDMA) 2000Evolution-Data Only (EV-DO) network, when LTE and LTE-A networks areotherwise unavailable.

In accordance with various embodiments described herein, the terms‘wireless communication device,’ ‘electronic device,’ ‘mobile device,’‘mobile station,’ ‘wireless station,’ ‘wireless access point,’‘station,’ ‘access point’ and ‘user equipment’ (UE) may be used hereinto describe one or more consumer electronic devices that may be capableof performing procedures associated with various embodiments of thedisclosure.

We now describe the communication technique. FIG. 1 presents a blockdiagram illustrating an example of electronic devices communicatingwirelessly. In particular, electronic device 110 (such as a smart-watchor a smart-phone) and electronic device 112 (such as a laptop computer,a notebook computer, a tablet, or another such electronic device) maycommunicate wirelessly using Bluetooth (such as BTLE) and/or in a WLANusing an IEEE 802.11 communication protocol (such as Wi-Fi and/or Wi-Fidirect). Moreover, electronic devices 110 and/or 112 may be associatedwith either of access points 114. For example, electronic devices 110and 112 may wirelessly communicate while: detecting one another byscanning wireless channels, transmitting and receiving beacons or beaconframes on wireless channels, establishing connections (for example, bytransmitting connect requests), and/or transmitting and receivingpackets or frames (which may include the request and/or additionalinformation, such as data, as payloads). Note that access points 114 mayprovide access to a network 116, such as the Internet, via an Ethernetprotocol, and may be a physical access point or a virtual or ‘software’access point that is implemented on a computer or an electronic device.

As described further below with reference to FIG. 4, electronic devices110 and 112 may include subsystems, such as a networking subsystem, amemory subsystem, and a processor subsystem. In addition, electronicdevices 110 and 112 may include radios 118 in the networking subsystems.More generally, electronic devices 110 and 112 can include (or can beincluded within) any electronic devices with networking subsystems thatenable electronic devices 110 and 112 to wirelessly communicate withanother electronic device. This can include transmitting beacons onwireless channels to enable the electronic devices to make initialcontact with or to detect each other, followed by exchanging subsequentdata/management frames (such as connect requests) to establish aconnection, configure security options (e.g., IPSec), transmit andreceive packets or frames via the connection, etc.

As can be seen in FIG. 1, wireless signals 120 (represented by a jaggedline) are communicated by radios 118-1 and 118-2 in electronic devices110 and 112, respectively. For example, as noted previously, electronicdevices 110 and 112 may exchange packets using BTLE and/or a Wi-Ficommunication protocol. In particular, electronic device 112 mayinitially be locked. Then, electronic device 112 may detect anaccess-intent operation. For example, a user may open a lid ofelectronic device 112 or the user may activate a human-interface devicein or associated with electronic device 112 (such as when the usertouches a physical or a virtual keyboard, moves a mouse, etc.). Inresponse, electronic device 112 may perform a wireless scan for otherelectronic devices in proximity or nearby (i.e., withinwireless-communication range) using BTLE.

Next, electronic device 112 may discover electronic device 110 bydetecting one or more BTLE advertising frames broadcast by electronicdevice 110. In response, electronic device 112 may establish aconnection with electronic device 110 using BTLE.

Moreover, electronic device 110 may transmit (and electronic device 112may receive) an identifier of electronic device 110 (such as a MACaddress of electronic device 110) and information specifying a preferredchannel of electronic device 110 when using a Wi-Fi communicationprotocol. As described further below, electronic device 112 may select achannel based at least on the preferred channel and communicationcontexts of electronic devices 110 and 112 (such as whether or notelectronic devices 110 and/or 112 have a connection to network 116 viathe same or different access points 114 or an intermediate device, thechannel(s) that they are using, etc.). In general, if electronic device110 has an active connection, electronic device 112 may select thepreferred channel as the channel to avoid disrupting any process(es) orapplication(s) executing on electronic device 110 during the wirelessranging described below. Furthermore, electronic device 112 may transmitan identifier of electronic device 112 (such as a MAC address ofelectronic device 112) and information specifying the selected channel.

Then, electronic devices 110 and 112 may access, on a remote computer(or server) 122 via one or more access points 114 and network 116,credential information associated with a user of electronic devices 110and 112 based on the identifiers. For example, the electronic devices110 and 112 may access a user account that specifies electronic devices110 and 112 and the associated credential information. Note that theuser account may be associated with a provider of electronic devices 110and 112. Moreover, the credential information may include encryptionkeys, a secure hashing function (such as a one-way hashing function),etc., that can be used to establish a secure connection betweenelectronic devices 110 and 112 and/or to encrypt one or more fields inframes that are communicated between electronic devices 110 and 112. Insome embodiments, the credential information includes login credentialsor login information for electronic device 112, such as a username andpassword.

Based on the credential information, electronic devices 110 and 112 mayset up a secure connection using the selected channel and the Wi-Ficommunication protocol (such as Wi-Fi direct). Additionally, electronicdevice 112 may determine a distance to electronic device 110 usingwireless ranging via the secure connection. (Alternatively oradditionally, electronic device 110 may determine the distance toelectronic device 112 using wireless ranging (or radio-based distancemeasurements) via the secure connection, and the determined distance maybe transmitted to electronic device 112.) Based on the determineddistance, electronic device 112 may be unlocked or access to electronicdevice 112 may be enabled. For example, if the distance is less than athreshold value (such as 0-3 m), electronic device 112 may be unlocked.In this way, electronic device 112 may not be inadvertently unlockedwhen electronic device 110 is in BTLE wireless-communication range butthe user is on the other side of a room, etc.

During wireless ranging, note that an electronic device (such aselectronic device 112) may transmit a frame or a packet that includes atransmission time. When this frame or packet is received by anotherelectronic device (such as electronic device 110), the arrival time maybe determined. Based on the product of the time of flight (thedifference of the arrival time and the transmission time) and the speedof propagation, the distance between electronic devices 110 and 112 canbe calculated. This distance may be communicated in a subsequenttransmission of a frame or a packet from electronic device 110 toelectronic device 112. Alternatively, electronic device 110 may transmita frame or a packet that includes a transmission time, and electronicdevice 112 may determine the distance between electronic devices 110 and112 based on the product of the time of flight (the difference of anarrival time and the transmission time) and the speed of propagation.Note that this approach for dynamically determining distances betweenelectronic devices that wirelessly communicate is sometimes referred toas ‘wireless ranging.’ Similarly, a variation on this approach in whichelectronic device 112 (or 110) transmits frames or packets that arereflected at electronic device 110 (or 112) may optionally be used todynamically determine the distance between electronic devices 110 and112. Thus, wireless ranging may be used by electronic devices 110 and/or112 to determine when another electronic device is proximate in anenvironment.

While the preceding example illustrated wireless ranging withsynchronized clocks in electronic devices 110 and 112, in otherembodiments the clocks are not synchronized. For example, the positionof electronic device 110 or 112 may be estimated based on the speed ofpropagation and the time of arrival data of wireless signals 120 atseveral receivers at different known locations (which is sometimesreferred to as ‘differential time of arrival’) even when thetransmission time is unknown or unavailable. More generally, a varietyof radiolocation techniques may be used, such as: determining distancebased on a difference in the power of the received signal strengthindicator (RSSI) relative to the original transmitted signal strength(which may include corrections for absorption, refraction, shadowingand/or reflection); determining the angle of arrival at a receiver(including non-line-of-sight reception) using a directional antenna orbased on the differential time of arrival at an array of antennas withknown location(s); determining the distance based on backscatteredwireless signals; and/or determining the angle of arrival at tworeceivers having known location (i.e., trilateration ormultilateration). Note that wireless signals 120 may includetransmissions over GHz or multi-GHz bandwidths to create pulses of shortduration (such as, e.g., approximately 1 ns), which may allow thedistance to be determined within 0.3 m (e.g., 1 ft). In someembodiments, the wireless ranging is facilitated using locationinformation, such as a location of one or more of electronic devices inFIG. 1 that are determined or specified by a local positioning system, aGlobal Positioning System and/or a wireless network.

In these ways, the communication technique may allow electronic device110 to be used to facilitate rapid access to 112 by performing wirelessaccess authentication. This capability may improve the user experiencewhen using electronic devices 110 and/or 112.

In the described embodiments, processing a packet or frame in one ofelectronic devices 110 and 112 includes: receiving wireless signals 120encoding a packet or a frame; decoding/extracting the packet or framefrom received wireless signals 120 to acquire the packet or frame; andprocessing the packet or frame to determine information contained in thepacket or frame (such as data in the payload).

In general, the communication in the communication technique may becharacterized by a variety of communication-performance metrics. Forexample, the communication-performance metric may include: a receivedsignal strength indicator (RSSI), a data rate, a data rate forsuccessful communication (which is sometimes referred to as a‘throughput’), a latency, an error rate (such as a retry or resendrate), a mean-square error of equalized signals relative to anequalization target, inter-symbol interference, multipath interference,a signal-to-noise ratio (SNR), a width of an eye pattern, a ratio ofnumber of bytes successfully communicated during a time interval (suchas 1-10 s) to an estimated maximum number of bytes that can becommunicated in the time interval (the latter of which is sometimesreferred to as the ‘capacity’ of a communication channel or link),and/or a ratio of an actual data rate to an estimated maximum data rate(which is sometimes referred to as ‘utilization’).

Although we describe the network environment shown in FIG. 1 as anexample, in alternative embodiments, different numbers and/or types ofelectronic devices may be present. For example, some embodiments mayinclude more or fewer electronic devices. As another example, in otherembodiments, different electronic devices can be transmitting and/orreceiving packets or frames.

FIG. 2 presents a flow diagram illustrating an example method 200 forfacilitating wireless access authentication in accordance with someembodiments. This method may be performed by an electronic device, suchas an interface circuit in electronic device 110 in FIG. 1. Duringoperation, the electronic device may detect an access-intent operation(operation 210), e.g., opening a device lid/cover or contacting aninterface device, such as a keyboard, mouse, or touch-input. Then, theelectronic device may establish a connection with a second electronicdevice (operation 212) using a communication protocol. For example,after detecting the access-intent operation (operation 210), theelectronic device may perform a wireless scan for the second electronicdevice using the communication protocol, and the electronic device maydiscover the second electronic device.

Moreover, the electronic device may receive, from the second electronicdevice, a second identifier of the second electronic device andinformation specifying a preferred channel (operation 214) of the secondelectronic device when using a second communication protocol.

Furthermore, the electronic device may select a channel (operation 216)based at least on the preferred channel and communication contexts ofthe electronic device and the second electronic device, and theelectronic device may transmit an identifier of the electronic deviceand information specifying the selected channel (operation 218). Notethat the communication contexts may include whether the electronicdevice has a connection to the network via an access point, and whetherthe second electronic device has a second connection to the network viathe same or a different access point or an intermediate device. When thesecond electronic device has the second connection, the electronicdevice may select the preferred channel as the channel.

Next, the electronic device may access, on a remote computer via anetwork, credential information (operation 220) associated with a userof the electronic device and the second electronic device based on theidentifier and the second identifier.

Additionally, the electronic device may set up, based on the credentialinformation, a secure connection (operation 222) with the secondelectronic device using the selected channel and the secondcommunication protocol.

Subsequently, the electronic device may determine a distance to thesecond electronic device (operation 224) using wireless ranging via thesecure connection, and the electronic device may be unlocked or accessto the electronic device may be enabled (operation 228) based on thedetermined distance. For example, if the distance is less than athreshold value (operation 226), the electronic device may be unlockedor access to the electronic device may be enabled (operation 228).Otherwise (operation 226), the electronic device may remain locked(operation 230).

Note that in some embodiments of methods 200, there may be additional orfewer operations. Moreover, the order of the operations may be changed,and/or two or more operations may be combined into a single operation.

In some embodiments, at least some of the operations in method areperformed by interface circuits in the electronic device and the secondelectronic device. For example, at least some of the operations may beperformed by firmware executed by an interface circuit, such as firmwareassociated with a MAC layer, as well as one or more circuits in aphysical layer in the interface circuit.

The communication techniques are further illustrated in FIG. 3, whichpresents a flow diagram illustrating an example of communication betweenelectronic device 110, electronic device 112, access point 114-1 andcomputer 122. In particular, processor 310 in electronic device 112 maydetect an access-intent operation 312. After detecting access-intentoperation 312, interface circuit 314 may perform a wireless scan 316 forelectronic device 110 using the communication protocol based oninstruction 308, and interface circuit 314 may discover 318 electronicdevice 110 based on advertisement 306 transmitted by interface circuit322 in electronic device 110. Then, interface circuit 314 may establisha connection 320 with interface circuit 322 using the communicationprotocol.

Moreover, interface circuit 322 may transmit an identifier 324 ofelectronic device 110 and information 326 specifying a preferred channelof electronic device 110 when using the second communication protocol,and identifier 324 and information 326 may be received by interfacecircuit 314.

Furthermore, processor 310 (or interface circuit 314) may select achannel 328 based at least on the preferred channel and communicationcontexts of electronic devices 110 and 112, and interface circuit 314may transmit an identifier 330 of electronic device 112 and information332 specifying the selected channel 328. The identifier 330 andinformation 332 may be received by interface circuit 322.

Next, interface circuits 314 and 322 may access, on computer 122,credential information 334 associated with a user of electronic devices110 and 112 based on identifiers 324 and 330.

Based on credential information 334, interface circuits 314 and 322 mayset up a secure connection 336 with each other using the selectedchannel 328 and the second communication protocol.

Subsequently, interface circuit 314 and/or 322 may determine a distance338 between electronic devices 110 and 112 using wireless ranging viasecure connection 336, and processor 310 may unlock 342 electronicdevice 112 based on login credentials (which may be included incredential information 334) and/or the determined distance 338, and,more generally, information 340 provided by interface circuit 314.

Representative Embodiments

We now describe embodiments of the communication technique. Wirelessaccess authentication poses several challenges. Notably, user loginneeds to be fast (otherwise, a user may not be willing to wait) andsecure to prevent spoofing or unauthorized access. However, it can bedifficult to quickly set up a secure connection, which may befrustrating to users.

In the communication technique, BTLE is used to bootstrap secure Wi-Ficommunication, which then performs the wireless access authentication.The total latency of the wireless access may be less than 1 or 2 s. Thiscapability may allow wireless access authentication to a wide variety ofelectronic devices, including legacy electronic devices that do notinclude a touch identifier (such as a fingerprint sensor). Consequently,the communication technique may eliminate the need for a user tomanually provide their password or login credentials, and may providerapid and secure access to the user's electronic device(s).

During the communication technique, a user may bring a smart-watch(which is sometimes referred to as a ‘key’) that is advertising usingBTLE frames in a band of frequencies (such as the 2.4 GHz band offrequencies) proximate to their laptop computer. Initially, the laptopcomputer may locked (e.g., displaying a locked screen). When the userlifts the lid of the laptop, touches a keyboard, moves a mouse and, moregenerally, provides an access-intent operation, the laptop computer mayperform a wireless scan. When the laptop computer detects a BTLE framewith an advertisement for the smart-watch, the laptop computer maydiscover the smart-watch. Then, the laptop computer may establish a BTLEconnection with the smart-watch. Note that the BTLE connection may ormay not be a secure connection.

After the BTLE connection is established, the smart-watch may send itsMAC address to the smart watch along with information specifying achannel that the smart-watch would prefer to use for IEEE802.11-compatible communication. Note that the laptop computer may becapable of communicating in one or more bands of frequencies (such asthe 2.4 GHz band of frequencies and the 5 GHz band of frequencies).

Next, the laptop computer may determine or select which channel to use.This determination may be based on the preferred channel of thesmart-watch and the communication contexts or states of the smart-watchand the laptop computer. In particular, the communication contexts mayinclude whether the smart-watch and/or the laptop computer have accessto the Internet via one or more access points (and/or intermediatedevices, such as the user's cellular telephone), e.g., theinfrastructure connectivity of the smart-watch and/or the laptopcomputer. Because the smart-watch may be more restricted in the band offrequencies it can use for communication, and in order to avoiddisrupting a data stream associated with an application executing on thesmart-watch by forcing the smart-watch to switch or hop betweenchannels, the preferred channel may be given priority in thedetermination if the smart-watch has a connection to the Internet via anaccess point and/or an intermediate device. This is illustrated in Table1, which presents an example of communication-context information forthe smart-watch and the laptop computer. In particular, if thesmart-watch is disconnected from the Internet and the laptop computer isalso disconnected, the laptop computer may perform a scan of a limitedset of channels (such as channels 1, 6 and 11, which may be commonacross multiple countries or regulatory regions) and may choose one ofthese channels as the channel (such as the least congested channel inthe limited set). Alternatively, if the smart-watch is (directly orindirectly) connected to an access point, the laptop computer may selectthe preferred channel of the smart-watch whether or not the laptopcomputer is connected to the same or a different access point.Furthermore, if the smart-watch is disconnected and the laptop isconnected using a channel in the 2.4 GHz band of frequencies, thischannel may be selected as the channel during the determination.However, if the smart-watch is disconnected and the laptop is connectedusing a channel in the 5 GHz band of frequencies, the laptop computermay perform a scan of the limited set of channels (such as channels 1, 6and 11) and may choose one of these channels as the channel (because thesmart-watch may not be able to operate in the 5 GHz band offrequencies).

TABLE 1 Smart-phone Laptop Infrastructure Infrastructure ConnectionStatus Connection Status Determined and Frequency Band and FrequencyBand Channel or Action Disconnected Disconnected Scan 1, 6 and 11Connected, 2.4 GHz Disconnected Use current smart-watch channelConnected, 2.4 GHz Connected, 2.4 or 5 GHz Use current smart-watchchannel Disconnected Connected, 2.4 GHz Use current laptop channelDisconnected Connected, 5 GHz Scan 1, 6 and 11

Next, the laptop computer may transmit its MAC address to thesmart-watch via the BTLE connection along with the selected channel.Moreover, the smart-watch and the laptop computer may, respectively,access a cloud-based account of the user with credential information forthe smart-watch and the laptop computer. For example, the smart-watchmay perform a look up in the cloud-based account based on the MACaddress for the laptop computer to obtain a public encryption key orsecure hashing table for the laptop computer. In some embodiments, thesmart-watch may also obtain login credentials (such as a username andpassword) for the laptop computer. Similarly, the laptop computer mayperform a look up in the cloud-based account based on the MAC addressfor the smart-watch to obtain a public encryption key or secure hashingtable for the smart-watch.

Using the credentials, the smart-watch and the laptop computer mayestablish a secure connection using the Wi-Fi communication protocol andthe selected channel. For example, the secure connection may use Wi-Fidirect, such as AWDL. Note that the information exchanged using BTLE mayspeed up the establishment of the secure connection between thesmart-watch and the laptop computer, thereby reducing the latency of thewireless access authentication.

Furthermore, using the secure connection, the laptop computer and/or thesmart-watch may determine the distance between the smart-watch and thelaptop computer via wireless ranging. If the distance is less than athreshold value (such as, e.g., 0-3 m), the laptop computer may beunlocked. Otherwise, the laptop computer may remain locked. In this way,the user can avoid inadvertently unlocking the laptop computer when theyare within BTLE communication range.

Note that the secure connection may be temporary. For example, it mayhave a duration of 1 s, so that there is sufficient time to determinethe distance using wireless ranging and to either unlock the laptopcomputer or not.

In the previous discussion, the user needs to be signed into thesmart-watch and the smart-watch needs to be active in order to performthe wireless access authentication. However, in some embodiments, thewireless access authentication is performed in the smart-watch wasunlocked and was recently locked (such as within the last 20 s). Thismay provide additional security by preventing unlocking of the laptopcomputer by merely bringing a locked smart-watch into proximity.

In some embodiments, another electronic device is used as the key. Forexample, the user may use their smart-phone, or tablet computer,notebook computer, wearable, or other computing such device. Inparticular, the user may have unlocked and been using their cellulartelephone to check their email, when they walk up to their laptopcomputer and put their (now locked) cellular telephone in their pocket.In this scenario, the user may still be able to unlock the laptop usingthe communication technique within a brief time interval (such as 20 s).Furthermore, in some embodiments, the ‘key’ may be used to unlock acomputing device other than a laptop, such as a smart-phone, a mediadevice, a notebook computer, a tablet computer, a wearable, a homeautomation device, or other such computing device.

Note that when another electronic device is used as the key, additionalbands of frequencies may be available. For example, the user's cellulartelephone or tablet computer may be able to communicate in the 2.4 GHzband of frequencies and the 5 GHz band of frequencies. In theseembodiments, the determination of the channel to be used in the securechannel may be modified. This is shown in Table 2, which presents anexample of communication-context information for the cellular telephoneand the laptop computer. In particular, if the cellular telephone isdisconnected from the Internet and the laptop computer is alsodisconnected, the laptop computer may perform a scan of a limited set ofchannels (such as channels 1, 6, 11, 44 and 149, which may be commonacross multiple countries or regulatory regions) and may choose one ofthese channels as the channel (such as the least congested channel inthe limited set). Alternatively, if the cellular telephone is connectedto the Internet, the laptop computer may select the preferred channel ofthe cellular telephone when the laptop computer is connected ordisconnected from the Internet. Furthermore, if the cellular telephoneis disconnected from the Internet and the laptop is connected using achannel in the 2.4 GHz band of frequencies, this channel may be selectedas the channel during the determination. Additionally, if the cellulartelephone is disconnected from the Internet and the laptop is connectedusing a channel in the 5 GHz band of frequencies, this channel may beselected as the channel during the determination.

TABLE 2 Cellular Telephone Laptop Infrastructure InfrastructureConnection Status Connection Status Determined and Frequency Band andFrequency Band Channel or Action Disconnected Disconnected Scan 1, 6,11, 44 and 149 Connected, 2.4 GHz Disconnected Use currentcellular-telephone channel Connected, 2.4 GHz Connected, 2.4 or 5 Usecurrent cellular-telephone GHz channel Disconnected Connected, 2.4 GHzUse current laptop channel Disconnected Connected, 5 GHz Use currentlaptop channel

As noted previously, by avoiding (when possible) channel switching orhoping by the cellular telephone, a data stream associated with anapplication executing on the cellular telephone may not be disrupted.For example, a video phone call can be handed off seamlessly to thelaptop computer without a dropped call or increased latency.

In some embodiments, the communication technique is used to performwireless access authentication for another electronic device, such as atablet computer, a television, etc.

We now describe embodiments of an electronic device. FIG. 4 presents ablock diagram of an electronic device 400 (which may be an access point,another electronic device, such as a station, a laptop computer, asmart-phone, a tablet, a smart-watch, etc.) in accordance with someembodiments. This electronic device includes processing subsystem 410,memory subsystem 412, and networking subsystem 414. Processing subsystem410 includes one or more devices configured to perform computationaloperations. For example, processing subsystem 410 can include one ormore microprocessors, application-specific integrated circuits (ASICs),microcontrollers, programmable-logic devices, and/or one or more digitalsignal processors (DSPs).

Memory subsystem 412 includes one or more devices for storing dataand/or instructions for processing subsystem 410 and networkingsubsystem 414. For example, memory subsystem 412 can include dynamicrandom access memory (DRAM), static random access memory (SRAM), aread-only memory (ROM), flash memory, and/or other types of memory. Insome embodiments, instructions for processing subsystem 410 in memorysubsystem 412 include: one or more program modules or sets ofinstructions (such as program module 422 or operating system 424), whichmay be executed by processing subsystem 410. For example, a ROM canstore programs, utilities or processes to be executed in a non-volatilemanner, and DRAM can provide volatile data storage, and may storeinstructions related to the operation of electronic device 400. Notethat the one or more computer programs may constitute a computer-programmechanism, a computer-readable storage medium or software. Moreover,instructions in the various modules in memory subsystem 412 may beimplemented in: a high-level procedural language, an object-orientedprogramming language, and/or in an assembly or machine language.Furthermore, the programming language may be compiled or interpreted,e.g., configurable or configured (which may be used interchangeably inthis discussion), to be executed by processing subsystem 410. In someembodiments, the one or more computer programs are distributed over anetwork-coupled computer system so that the one or more computerprograms are stored and executed in a distributed manner.

In addition, memory subsystem 412 can include mechanisms for controllingaccess to the memory. In some embodiments, memory subsystem 412 includesa memory hierarchy that comprises one or more caches coupled to a memoryin electronic device 400. In some of these embodiments, one or more ofthe caches is located in processing subsystem 410.

In some embodiments, memory subsystem 412 is coupled to one or morehigh-capacity mass-storage devices (not shown). For example, memorysubsystem 412 can be coupled to a magnetic or optical drive, asolid-state drive, or another type of mass-storage device. In theseembodiments, memory subsystem 412 can be used by electronic device 400as fast-access storage for often-used data, while the mass-storagedevice is used to store less frequently used data.

Networking subsystem 414 includes one or more devices configured tocouple to and communicate on a wired and/or wireless network (i.e., toperform network operations), including: control logic 416, an interfacecircuit 418 and a set of antennas 420 (or antenna elements) in anadaptive array that can be selectively turned on and/or off by controllogic 416 to create a variety of optional antenna patterns or ‘beampatterns.’ (While FIG. 4 includes set of antennas 420, in someembodiments electronic device 400 includes one or more nodes, such asnodes 408, e.g., a pad, which can be coupled to set of antennas 420.Thus, electronic device 400 may or may not include set of antennas 420.)For example, networking subsystem 414 can include a Bluetooth™networking system, a cellular networking system (e.g., a 3G/4G/5Gnetwork such as UMTS, LTE, etc.), a universal serial bus (USB)networking system, a networking system based on the standards describedin IEEE 802.11 (e.g., a Wi-Fi® networking system), an Ethernetnetworking system, and/or another networking system.

Networking subsystem 414 includes processors, controllers,radios/antennas, sockets/plugs, and/or other devices used for couplingto, communicating on, and handling data and events for each supportednetworking system. Note that mechanisms used for coupling to,communicating on, and handling data and events on the network for eachnetwork system are sometimes collectively referred to as a ‘networkinterface’ for the network system. Moreover, in some embodiments a‘network’ or a ‘connection’ between the electronic devices does not yetexist. Therefore, electronic device 400 may use the mechanisms innetworking subsystem 414 for performing simple wireless communicationbetween the electronic devices, e.g., transmitting advertising or beaconframes and/or scanning for advertising frames transmitted by otherelectronic devices.

Within electronic device 400, processing subsystem 410, memory subsystem412, and networking subsystem 414 are coupled together using bus 428that facilitates data transfer between these components. Bus 428 mayinclude an electrical, optical, and/or electro-optical connection thatthe subsystems can use to communicate commands and data among oneanother. Although only one bus 428 is shown for clarity, differentembodiments can include a different number or configuration ofelectrical, optical, and/or electro-optical connections among thesubsystems.

In some embodiments, electronic device 400 includes a display subsystem426 for displaying information on a display, which may include a displaydriver and the display, such as a liquid-crystal display, a multi-touchtouchscreen, etc. Display subsystem 426 may be controlled by processingsubsystem 410 to display information to a user (e.g., informationrelating to incoming, outgoing, or an active communication session).

Electronic device 400 can also include a user-input subsystem 430 thatallows a user of the electronic device 400 to interact with electronicdevice 400. For example, user-input subsystem 430 can take a variety offorms, such as: a button, keypad, dial, touch screen, audio inputinterface, visual/image capture input interface, input in the form ofsensor data, etc.

Electronic device 400 can be (or can be included in) any electronicdevice with at least one network interface. For example, electronicdevice 400 may include: a cellular telephone or a smart-phone, a tabletcomputer, a laptop computer, a notebook computer, a personal or desktopcomputer, a netbook computer, a media player device, an electronic bookdevice, a MiFi® device, a smart-watch, a wearable computing device, aportable computing device, a consumer-electronic device, an accesspoint, a router, a switch, communication equipment, test equipment, aswell as any other type of electronic computing device having wirelesscommunication capability that can include communication via one or morewireless communication protocols.

Although specific components are used to describe electronic device 400,in alternative embodiments, different components and/or subsystems maybe present in electronic device 400. For example, electronic device 400may include one or more additional processing subsystems, memorysubsystems, networking subsystems, and/or display subsystems.Additionally, one or more of the subsystems may not be present inelectronic device 400. Moreover, in some embodiments, electronic device400 may include one or more additional subsystems that are not shown inFIG. 4. Also, although separate subsystems are shown in FIG. 4, in someembodiments some or all of a given subsystem or component can beintegrated into one or more of the other subsystems or component(s) inelectronic device 400. For example, in some embodiments program module422 is included in operating system 424 and/or control logic 416 isincluded in interface circuit 418.

Moreover, the circuits and components in electronic device 400 may beimplemented using any combination of analog and/or digital circuitry,including: bipolar, PMOS and/or NMOS gates or transistors. Furthermore,signals in these embodiments may include digital signals that haveapproximately discrete values and/or analog signals that have continuousvalues. Additionally, components and circuits may be single-ended ordifferential, and power supplies may be unipolar or bipolar.

An integrated circuit (which is sometimes referred to as a‘communication circuit’) may implement some or all of the functionalityof networking subsystem 414. This integrated circuit may includehardware and/or software mechanisms that are used for transmittingwireless signals from electronic device 400 and receiving signals atelectronic device 400 from other electronic devices. Aside from themechanisms herein described, radios are generally known in the art andhence are not described in detail. In general, networking subsystem 414and/or the integrated circuit can include any number of radios. Notethat the radios in multiple-radio embodiments function in a similar wayto the described single-radio embodiments.

In some embodiments, networking subsystem 414 and/or the integratedcircuit include a configuration mechanism (such as one or more hardwareand/or software mechanisms) that configures the radio(s) to transmitand/or receive on a given communication channel (e.g., a given carrierfrequency). For example, in some embodiments, the configurationmechanism can be used to switch the radio from monitoring and/ortransmitting on a given communication channel to monitoring and/ortransmitting on a different communication channel. (Note that‘monitoring’ as used herein comprises receiving signals from otherelectronic devices and possibly performing one or more processingoperations on the received signals.)

In some embodiments, an output of a process for designing the integratedcircuit, or a portion of the integrated circuit, which includes one ormore of the circuits described herein may be a computer-readable mediumsuch as, for example, a magnetic tape or an optical or magnetic disk.The computer-readable medium may be encoded with data structures orother information describing circuitry that may be physicallyinstantiated as the integrated circuit or the portion of the integratedcircuit. Although various formats may be used for such encoding, thesedata structures are commonly written in: Caltech Intermediate Format(CIF), Calma GDS II Stream Format (GDSII) or Electronic DesignInterchange Format (EDIF). Those of skill in the art of integratedcircuit design can develop such data structures from schematic diagramsof the type detailed above and the corresponding descriptions and encodethe data structures on the computer-readable medium. Those of skill inthe art of integrated circuit fabrication can use such encoded data tofabricate integrated circuits that include one or more of the circuitsdescribed herein.

While the preceding discussion used BTLE and a Wi-Fi directcommunication protocol as illustrative examples, in other embodiments awide variety of communication protocols and, more generally, wirelesscommunication techniques may be used. Thus, the communication techniquemay be used in a variety of network interfaces. Furthermore, while someof the operations in the preceding embodiments were implemented inhardware or software, in general the operations in the precedingembodiments can be implemented in a wide variety of configurations andarchitectures. Therefore, some or all of the operations in the precedingembodiments may be performed in hardware, in software or both. Forexample, at least some of the operations in the communication techniquemay be implemented using program module 422, operating system 424 (suchas a driver for interface circuit 418) or in firmware in interfacecircuit 418. Alternatively or additionally, at least some of theoperations in the communication technique may be implemented in aphysical layer, such as hardware in interface circuit 418. In someembodiments, the communication technique is implemented, at least inpart, in a MAC layer and/or in a physical layer in interface circuit418.

In some embodiments, an electronic device includes: one or more nodesconfigured to communicatively couple to an antenna; and an interfacecircuit, communicatively coupled to the one or more nodes, configured tocommunicate with a second electronic device, and configured to cause theelectronic device to: (i) detect an access-intent operation; (ii)establish, based at least in part on the access-intent operation, aconnection with the second electronic device using a communicationprotocol; (iii) receive, from the second electronic device, a secondidentifier of the second electronic device and information specifying apreferred channel of the second electronic device when using a secondcommunication protocol; (iv) select a channel based at least in part onthe preferred channel of the second electronic device and based at leastin part on communication contexts of the electronic device and thesecond electronic device; (v) transmit, to the second electronic device,an identifier of the electronic device and information specifying theselected channel; (vi) access, from a remote computer via a network,credential information associated with a user of the electronic deviceand the second electronic device based on the identifier and the secondidentifier; (vii) establish, based at least in part on the credentialinformation, a secure connection with the second electronic device usingthe selected channel and the second communication protocol; (viii)determine a distance to the second electronic device using wirelessranging via the secure connection; and (ix) enable access to theelectronic device based at least in part on the determined distance.

In some embodiments, the interface circuit is further configured tocause the electronic device to: perform, based at least in part on theaccess-intent operation, a wireless scan for the second electronicdevice using the communication protocol; and discover the secondelectronic device. In some embodiments, the electronic device detectsthe access-intent operation by one or more of: opening a lid of theelectronic device, or contacting a human-interface device associatedwith the electronic device. In some embodiments, the identifier includesa media access control (MAC) address of the electronic device, and thesecond identifier includes a second MAC address of the second electronicdevice. In some embodiments, the communication contexts include:information indicating whether the electronic device has a connection tothe network via an access point, and information indicating whether thesecond electronic device has a second connection to the network via thesame access point or via an intermediate device. In some embodiments,when the second electronic device has the second connection, theelectronic device selects the preferred channel as the channel. In someembodiments, the communication protocol is compatible with a BluetoothLow Energy (BTLE) communication protocol, and the second communicationprotocol is compatible with an IEEE 802.11 standardized communicationprotocol. In some embodiments, the electronic device includes one of: alaptop computer, a tablet computer, or a cellular telephone.

In some embodiments, a non-transitory computer-readable storage mediumstores instructions that, when executed by an interface circuit includedin a laptop computer, cause the laptop computer to facilitate wirelessaccess authentication, by carrying out one or more operations thatinclude: (i) detecting an access-intent operation; (ii) establishing,based at least in part on the access-intent operation, a connection witha second electronic device using a Bluetooth-compatible communicationprotocol; (iii) receiving, from the second electronic device, a secondidentifier of the second electronic device and information specifying apreferred channel of the second electronic device for use with aWi-Fi-compatible communication protocol; (iv) selecting a channel basedat least in part on the preferred channel of the second electronicdevice; (v) transmitting, to the second electronic device, an identifierof the laptop computer and information specifying the selected channel;(vi) accessing, from a remote computer via a network, credentialinformation associated with a user of the laptop computer and the secondelectronic device based on the second identifier; (vii) establishing,based at least in part on the credential information, a secureconnection with the second electronic device using the selected channeland the Wi-Fi-compatible communication protocol; (viii) determining adistance to the second electronic device using wireless ranging via thesecure connection; and (ix) enabling access to the laptop computer basedat least in part on the determined distance.

In some embodiments, the one or more operations further include:performing, based at least in part on the access-intent operation, awireless scan for the second electronic device using theBluetooth-compatible communication protocol; and discovering the secondelectronic device. In some embodiments, the laptop computer detects theaccess-intent operation by one or more of: detecting an opening of a lidof the laptop computer, or detecting input to a human-interface deviceassociated with the laptop computer. In some embodiments, the identifierincludes a media access control (MAC) address of the laptop computer,and the second identifier includes a second MAC address of the secondelectronic device. In some embodiments, the laptop computer selects thechannel further based at least in part on communication contexts thatinclude: information indicating whether the laptop computer has aconnection to the network via an access point, and informationindicating whether the second electronic device has a second connectionto the network via the same access point or via an intermediate device.In some embodiments, when the second electronic device has the secondconnection, the laptop computer selects the preferred channel as thechannel.

In some embodiments, a method for facilitating wireless accessauthentication includes using an interface circuit in an electronicdevice to perform actions that include: (i) detecting an access-intentoperation; (ii) establishing, based at least in part on theaccess-intent operation, a connection with the second electronic deviceusing a communication protocol; (iii) receiving, from the secondelectronic device, a second media access control (MAC) address of thesecond electronic device and information specifying a preferred channelof the second electronic device when using a second communicationprotocol; (iv) selecting a channel based at least on the preferredchannel of the second electronic device and based at least in part oncommunication contexts of the electronic device and the secondelectronic device; (v) transmitting, to the second electronic device, aMAC address of the electronic device and information specifying theselected channel; (vi) accessing, from a remote computer via a network,credential information associated with a user of the electronic deviceand the second electronic device based at least in part on the MACaddress and the second MAC address; (vii) establishing, based at leastin part on the credential information, a secure connection with thesecond electronic device using the selected channel and the secondcommunication protocol; (viii) determining a distance to the secondelectronic device using wireless ranging via the secure connection; and(ix) unlocking the electronic device based at least in part on thedetermined distance.

In some embodiments, the method further includes: performing, based atleast in part on the access-intent operation, a wireless scan for thesecond electronic device using the communication protocol; anddiscovering the second electronic device. In some embodiments, detectingthe access-intent operation includes one or more of: detecting anopening of a lid of the electronic device, or detecting an input to ahuman-interface device associated with the electronic device. In someembodiments, the communication contexts include: information indicatingwhether the electronic device has a connection to the network via anaccess point, and information indicating whether the second electronicdevice has a second connection to the network via the same access pointor via an intermediate device. In some embodiments, when the secondelectronic device has the second connection, the electronic deviceselects the preferred channel as the channel. In some embodiments, thecommunication protocol is compatible with a Bluetooth Low Energy (BTLE)communication protocol, and the second communication protocol iscompatible with an IEEE 802.11 standardized communication protocol.

In the preceding description, we refer to ‘some embodiments.’ Note that‘some embodiments’ describes a subset of all of the possibleembodiments, but does not always specify the same subset of embodiments.

The foregoing description is intended to enable any person skilled inthe art to make and use the disclosure, and is provided in the contextof a particular application and its requirements. Moreover, theforegoing descriptions of embodiments of the present disclosure havebeen presented for purposes of illustration and description only. Theyare not intended to be exhaustive or to limit the present disclosure tothe forms disclosed. Accordingly, many modifications and variations willbe apparent to practitioners skilled in the art, and the generalprinciples defined herein may be applied to other embodiments andapplications without departing from the spirit and scope of the presentdisclosure. Additionally, the discussion of the preceding embodiments isnot intended to limit the present disclosure. Thus, the presentdisclosure is not intended to be limited to the embodiments shown, butis to be accorded the widest scope consistent with the principles andfeatures disclosed herein.

What is claimed is:
 1. An electronic device, comprising: one or morenodes configured to communicatively couple to an antenna; and aninterface circuit, communicatively coupled to the one or more nodes,configured to communicate with a second electronic device, andconfigured to cause the electronic device to: detect an access-intentoperation; establish, based at least in part on the access-intentoperation, a connection with the second electronic device using acommunication protocol; receive, from the second electronic device, asecond identifier of the second electronic device and informationspecifying a preferred channel of the second electronic device whenusing a second communication protocol; select a channel based at leastin part on the preferred channel of the second electronic device andbased at least in part on communication contexts of the electronicdevice and the second electronic device; transmit, to the secondelectronic device, an identifier of the electronic device andinformation specifying the selected channel; access, from a remotecomputer via a network, credential information associated with a user ofthe electronic device and the second electronic device based on theidentifier and the second identifier; establish, based at least in parton the credential information, a secure connection with the secondelectronic device using the selected channel and the secondcommunication protocol; determine a distance to the second electronicdevice using wireless ranging via the secure connection; and enableaccess to the electronic device based at least in part on the determineddistance.
 2. The electronic device of claim 1, wherein the interfacecircuit is further configured to cause the electronic device to:perform, based at least in part on the access-intent operation, awireless scan for the second electronic device using the communicationprotocol; and discover the second electronic device.
 3. The electronicdevice of claim 1, wherein the electronic device detects theaccess-intent operation by one or more of: detecting an opening of a lidof the electronic device, or detecting input to a human-interface deviceassociated with the electronic device.
 4. The electronic device of claim1, wherein: the identifier includes a media access control (MAC) addressof the electronic device, and the second identifier includes a secondMAC address of the second electronic device.
 5. The electronic device ofclaim 1, wherein the communication contexts include: informationindicating whether the electronic device has a connection to the networkvia an access point, and information indicating whether the secondelectronic device has a second connection to the network via the accesspoint or via an intermediate device.
 6. The electronic device of claim5, wherein, when the second electronic device has the second connection,the electronic device selects the preferred channel as the channel. 7.The electronic device of claim 1, wherein: the communication protocol iscompatible with a wireless personal area network communication protocol,and the second communication protocol is compatible with a wirelesslocal area network communication protocol.
 8. The electronic device ofclaim 1, wherein the electronic device includes one of: a laptopcomputer, a tablet computer, or a cellular telephone.
 9. Anon-transitory computer-readable storage medium storing instructionsthat, when executed by an interface circuit included in a laptopcomputer, cause the laptop computer to facilitate wireless accessauthentication, by carrying out one or more operations that comprise:detecting an access-intent operation; establishing, based at least inpart on the access-intent operation, a connection with a secondelectronic device using a wireless personal area network communicationprotocol; receiving, from the second electronic device, a secondidentifier of the second electronic device and information specifying apreferred channel of the second electronic device for use with awireless local area network communication protocol; selecting a channelbased at least in part on the preferred channel of the second electronicdevice; transmitting, to the second electronic device, an identifier ofthe laptop computer and information specifying the selected channel;accessing, from a remote computer via a network, credential informationassociated with a user of the laptop computer and the second electronicdevice based on the second identifier; establishing, based at least inpart on the credential information, a secure connection with the secondelectronic device using the selected channel and the wireless local areanetwork communication protocol; determining a distance to the secondelectronic device using wireless ranging via the secure connection; andenabling access to the laptop computer based at least in part on thedetermined distance.
 10. The non-transitory computer-readable storagemedium of claim 9, wherein the one or more operations further comprise:performing, based at least in part on the access-intent operation, awireless scan for the second electronic device using the wirelesspersonal area network communication protocol; and discovering the secondelectronic device.
 11. The non-transitory computer-readable storagemedium of claim 9, wherein the laptop computer detects the access-intentoperation by one or more of: detecting an opening of a lid of the laptopcomputer, or detecting input to a human-interface device associated withthe laptop computer.
 12. The non-transitory computer-readable storagemedium of claim 9, wherein: the identifier includes a media accesscontrol (MAC) address of the laptop computer, and the second identifierincludes a second MAC address of the second electronic device.
 13. Thenon-transitory computer-readable storage medium of claim 9, wherein thelaptop computer selects the channel further based at least in part oncommunication contexts that include: information indicating whether thelaptop computer has a connection to the network via an access point, andinformation indicating whether the second electronic device has a secondconnection to the network via the access point or via an intermediatedevice.
 14. The non-transitory computer-readable storage medium of claim13, wherein, when the second electronic device has the secondconnection, the laptop computer selects the preferred channel as thechannel.
 15. A method for facilitating wireless access authentication,the method comprising: using an interface circuit in an electronicdevice: detecting an access-intent operation; establishing, based on theaccess-intent operation, a connection with a second electronic deviceusing a communication protocol; receiving, from the second electronicdevice, a second media access control (MAC) address of the secondelectronic device and information specifying a preferred channel of thesecond electronic device when using a second communication protocol;selecting a channel based at least in part on the preferred channel ofthe second electronic device and based at least in part on communicationcontexts of the electronic device and the second electronic device;transmitting, to the second electronic device, a MAC address of theelectronic device and information specifying the selected channel;accessing, from a remote computer via a network, credential informationassociated with a user of the electronic device and the secondelectronic device based on the MAC address and the second MAC address;establishing, based at least in part on the credential information, asecure connection with the second electronic device using the selectedchannel and the second communication protocol; determining a distance tothe second electronic device using wireless ranging via the secureconnection; and unlocking the electronic device based at least in parton the determined distance.
 16. The method of claim 15, wherein themethod further comprises: performing, based at least in part on theaccess-intent operation, a wireless scan for the second electronicdevice using the communication protocol; and discovering the secondelectronic device.
 17. The method of claim 15, wherein detecting theaccess-intent operation includes one or more of: detecting an opening ofa lid of the electronic device, or detecting input to a human-interfacedevice associated with the electronic device.
 18. The method of claim15, wherein the communication contexts include: information indicatingwhether the electronic device has a connection to the network via anaccess point, and information indicating whether the second electronicdevice has a second connection to the network via the access point orvia an intermediate device.
 19. The method of claim 18, wherein, whenthe second electronic device has the second connection, the electronicdevice selects the preferred channel as the channel.
 20. The method ofclaim 15, wherein the communication protocol is compatible with awireless personal area network communication protocol, and the secondcommunication protocol is compatible with a wireless local area networkcommunication protocol.